After inspections and administrative delays, the Canadian ship tried to leave for Gaza on Monday but was quickly turned back to shore by the Greek coast guard.

Organizer David Heap, who was aboard the Tahrir, said he's disappointed the ship wasn't able to bring aid to Gaza.

But the group succeeded in drawing attention to the conditions there, he said.

"Obviously some individuals are disappointed," he told The Canadian Press in a phone interview from Greece on Saturday.

"But we have had remarkable success.. in getting this issue into the spotlight."

Several other boats that were part of a flotilla to Gaza have also dropped out, but organizers say some ships may still try to make the voyage.

Organizers have attributed Greece's hardline stance to Israeli pressure. The country is mired in an economic crisis and has grown closer to Israel as it seeks more foreign investment.

While many of the Canadian activists are already headed home, a Montreal-based organizer said this is only the beginning of an effort to bring attention to Israel's blockade of the Gaza Strip.

"We will start planning for the next phase and how to continue work with our workers," Ehab Lotayef said in an interview.

"I can't give any time frame at this point."

Critics have argued the mission supports Hamas, which governs the Gaza Strip and is classified as a terror organization in Canada and the United States.

But Lotayef said the flotilla has had no dealings with Hamas and is focused on the people who live in Gaza.

"This is a civil-society-to-civil-society initiative," he said.

The Harper government, however, has remained critical of the flotilla.

Foreign Minister John Baird has called the mission "provocative" and "unhelpful."

He has also urged those wishing to deliver humanitarian goods to Gaza to do so through established channels such as the International Committee of the Red Cross/Red Crescent.

"Canada recognizes Israel's legitimate security concerns and its right to protect itself and its residents from attacks by Hamas and other terrorist groups, including by preventing the smuggling of weapons," Baird said in a May statement.
Israel has warned it would stop any attempt to circumvent its restrictions.

A similar flotilla last year ended in bloodshed, when nine people were killed and 45 were injured after Israeli soldiers boarded a Turkish ship.